Squid
2 of the 6 encyclopedias on this shelf carry an entry for Squid. Both are reproduced below, so you can see where they agree and where they differ.
Aiton's Encyclopedia (1910)
a marine animal allied to the cuttlefish. The calamar, or squid, has ten arms, two of which are longer than the others. The body is elongated and tapers toward the posterior end. Near the posterior end are two fin-like flaps of skin, one on each side. Inside the body is a narrow, pen-shaped shell, which is somewhat horny but very easily bent. The squid, like the cuttlefish, is able to squirt a dark colored fluid about in the water, to the confusion of its enemies. It lives in temperate as well as in warm regions of the ocean. It is represented by several groups of species. The smallest squid is not to exceed an inch in length. The giant squid has an arm spread of fifty feet. The common squid reaches a length of two feet or more. It is bluish or purple in color. In the Mediterranean is found a species which, when full-grown, is about ten inches in length, and white, almost transparent in color. When frightened or captured it assumes a delicate pink or rose color, the tints being deepest over its back or dorsal side. The fins are used in swimming rapidly through the water, and it seems a creature of almost unearthly beauty, so delicate is its form and color. Squids are found in great numbers along both shores of North America . All squids are fish eaters. They hunt at night; darting backward into a school of mackerel like arrows, they create havoc. See Cuttlefish ; Octopus
Collier's New Encyclopedia (1921)
a popular name of certain cuttle fishes belonging to the dibranchiate group of the class Cephalopoda, and included in several genera, of which the most familiar is that of the calamaries.
What Has Changed in the Last Century
Aiton's 1910 account describes the squid entirely as a curiosity of the sea; the biggest scientific development since is that the squid's giant nerve fibre, thick enough to push electrodes into, let Alan Hodgkin and Andrew Huxley work out how nerve impulses travel, work that won them a share of the 1963 Nobel Prize and still underpins neuroscience. The "giant squid" with its fifty-foot arm spread was known in 1910 only from strandings and stomach contents of sperm whales; it was not photographed alive until 2004 and not filmed in its deep-water home until 2012, and it has since been displaced as the heaviest species by the colossal squid, Mesonychoteuthis, described in 1925. Collier's 1921 filing of squid among the "dibranchiate" cuttlefishes reflects a division no longer used, squid now sitting in the ten-armed Decapodiformes, separate from the true cuttlefishes. Aiton's claim that "all squids are fish eaters" is too narrow, many take crustaceans and other squid, and squid are now a global fishery of several million tonnes a year rather than mainly bait.
Written for this edition, 2026.